On average, listings lease in the $10's per square foot per year. The Oregon City region is seeing a decline in rates. In the last 3 months, the median rate decreased $6 per sqft per year. That's a 25% decrease in rent.
Compared to the rest of the Greater Portland market, the Oregon City region has smaller rates, so you should have no trouble finding a great deal in this discounted region.
In the last 90 days, 3 listings have come on the market, which means leases most likley are going fast. You'll want to be prepared to tour spaces as quick as possible. There aren't many listings below 2,000 square feet on the market, so finding a space for a small business might be tough.
The standard measurement for office space in this area is around 500 sqft. Most properties in this area are approximately 1 stories. Most buildings in this region were built in 1991 and are Class B.